Lists of planets

High school (ages 12+)
Space & Astronomy

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/lists-of-planets

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. Who discovered Lists of planets?Kepler Space Telescope and Transiting Exoplanet Survey Satellite (TESS)
2. What is the number of confirmed exoplanets?6,042 as of October 30, 2025
3. What is the number of multi-planet systems?1,020
4. What are the eight planets in our solar system?The eight planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
5. How do scientists find planets outside our solar system?They use space telescopes like Kepler and TESS, which watch stars for tiny dimming when a planet passes in front of the star.

Hydrostatic Equilibrium: A state where the inward pull of gravity is balanced by the outward push of internal pressure, resulting in a round shape.
Protoplanetary Disk: A rotating disk of gas and dust surrounding a young star, from which planets form through accretion.
Transit Photometry: A method of detecting exoplanets by measuring the periodic decrease in a star's brightness as a planet passes in front of it.
Habitable Zone: The region around a star where conditions might be right for liquid water to exist on a planet's surface.